What is the air quality in San Juan?

San Juan, Puerto Rico has an annual US AQI of 43 (Reasonable) and average PM2.5 of 7.9 µg/m³, ranking #376 of 5856 cities. Main pollutant: PM2.5.

What is the cleanest month in San Juan?

December is typically the cleanest month (AQI 35) and June the most polluted (AQI 52).

Where does San Juan's air quality data come from?

PM2.5: 1998–2025 (monitors 1999–2025, satellite 1998, 2009–2011, 2014–2015, 2017–2018, 2020–2024). Measured by government monitoring stations. Full sources are on the methodology page.

San Juan, Puerto Rico — Air Quality & Clean City Guide 2026

San Juan Air Quality Data

Global rank	City	Continent	AQI	PM2.5
376	San Juan, Puerto Rico	North America	AQI 43	PM2.5 7.9 µg/m³